1.1 KiB
I did some performance testing.
The Pro Micro runs an Atmel 32u4 at 8MHz. If the code does nothing else, I was able to poll all pins around 13 times every 1ms, or 13kHz.
Sample Rate
The number of samples taken since the last HID report is sent as the second Y axis. If you use the included gamepad tester, it will show the approximate number of samples as an integer, for Y axis 2.
This is approximate, because the browser encodes the value as a real number between -1 and 1. We convert it back, but may lose a little precision. It's close enough for me, hopefully it's close enough for you.
Debouncing
Using millis() time to debounce the switch
roughly halved my sample frequency.
So instead, I do some preprocessor arithmetic
to calculate how many samples to take after an edge,
in order to debounce switches.
The drum controller was a partcular pain: in addition to the switch bouncing, the stick was bouncing on the rubber pad. I settled on a 40ms silence window as feeling pretty good. You can adjust this if you want to.